What type of email server are you migrating from? We cannot pull all contact, calendar, task and notes from some email servers.

It is an older version of SmarterMail.

If you are running SmarterMail 6 or below you will want to upgrade to version 7 first and them follow the knowledge base article below to move your users, email, contact, calendars, etc if you are moving to a version that is version 7 or higher.

 

https://portal.smartertools.com/kb/a2724/migrate-smartermail-to-a-different-server.aspx

Old server --> SmarterMail Web Client 10.7.4842

New server --> SmarterMail Enterprise 13.3

Shouldn't it work?

If you have access to the file structure then it would be best to just copy the hard files and restore them on the new server.